■ Tapping Torque Equation for Forming Taps

Based on the tensile strength of workpiece material, we prepare following equation to obtain tapping torque of standard formig taps. Condition : Effective length of internal screw is 1.5D. Thread height is 75%.

Tapping Torque Equation for Forming TapsWorkpiece MaterialsDeforming resistance (N/mm 2)
General Structure Steels, Low Carbon Steels750~850
Medium Carbon Steels, Alloy Steels1150~1350
Stainless Steels1100~1300
T : Tapping Torque (N-m) Dc : Nominal Diameter of Tap (mm)Wrought Aluminum250~350
P : Pitch (mm)Aluminum Die Castings380~530
Kf : Deforming resistance (N/mm 2)Coppers, Wrought Copper Alloys750~1050